PTL 1 which is noted below describes an invention which, when an abnormality arises in an electronic-circuit-component mounting machine, presents a cause of the abnormality. The invention of PTL 1 stores an occurrence state of a mounting mistake of a component in the electronic-circuit-component mounting machine in a memory device, converts a correspondence relationship between the occurrence state of the mounting mistake and the cause thereof into an expression, and, when a mounting mistake actually occurs, estimates the cause based on the expression; in particular, the invention amends the expression of the correspondence relationship according to the environment in which the device is installed.
PTL 2 which is noted below describes an invention which, from time series data obtained by performing sequential observations over time of equipment and the like which forms a plant, sets two items of data for which it is estimated that there is a causal relationship therebetween as input data and output data, extracts information relating to responsiveness of the output data with respect to the input data for each type of variation unique to a control system such as a rising trend, a falling trend, or an oscillating trend of the input data, and acquires candidates of abnormality data from a deviation of the information relating to the responsiveness.